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51.
A non-rotational (NR) shot is now a well-known scoring move in soccer. To execute the NR shot, it is necessary to deprive the ball of any rotational forces during the impact phase. To execute the NR shot, it is natural that the force vector acting from the foot would pass through the ball’s center of gravity; however, the coordinated motion of the lower limb joint’s angular displacement and the pelvis is still unclear. The aim of this study is to estimate the coordinated leg and pelvis motion during the NR shot as compared to that during instep kicking. Four right-leg dominant college league players were asked to perform a NR shot and an instep kick a total of 10 times each. Hip, knee, and ankle joint angular displacements in the sagittal plane and pelvis yaw and roll rotational motions during both types of kicks were calculated with 14 IR reflective markers using a 3D real-time motion analysis system with a 250-Hz sampling. The Euclidean distances of the joint space of the NR shot and the instep kick were also calculated to detect similarities in the coordinated motion of the lower limb. The results showed that the lower limb joint motions in the sagittal plane were not different; however, the pelvis roll and yaw motions were apparently different, and these phenomena could simulate a pendulum motion with changes in both the vertical and horizontal displacements. These results suggest that the coordinated motion of the lower limb joint’s angular displacement shows high similarity between the NR shot and the instep kick, and the pelvis roll and yaw synchronized orientation is essential for achieving the NR shot. 相似文献
52.
David S. Haydon Ross A. Pinder Paul N. Grimshaw William S. P. Robertson 《Sports Engineering》2016,19(3):177-184
Limited recommendations of wheelchair configurations for court sports have been identified in the published literature. To accommodate the wide range of impairments in wheelchair rugby, players are given a point score that reflects their impairment. Players have regularly been grouped as high-, mid-, or low-point players in research, with high-point players having greater levels of muscle function compared with other classifications. This research documented the wheelchair configurations of elite Australian wheelchair rugby players across classification groups. Significant differences (p < 0.05) were found for increased seat height and decreased seat depth for high-point players compared with low- and mid-point groups, respectively. Low-point players displayed reduced wheelchair mass compared with high- and mid-point players, as well as increased frame length. Camber angles showed no significant differences across the classification groups. The incorporation of anthropometric measures, such as the elbow angle at the top dead center, was also investigated. While elbow angle showed no significant differences, seat height-to-total arm length ratio was higher for high-point players. Participants also completed surveys detailing their perception of the effect of altering wheelchair configurations. It is suggested that wheelchair configurations should consider an individual’s anthropometrics, impairment, training history, and court role to promote optimal performance, with predictive modeling having the potential to reduce the associated time and cost. 相似文献
53.
This research examines 441 front-page images published in 367 newspapers on the day following the shooting in Paris of 12 people at or near the Charlie Hebdo office. The aim of this study is to understand how mainstream media visually framed responsibility for the Charlie Hebdo massacre and how these visual frames coalesced to represent collective narratives about press freedom. Through a collaborative visual analysis, this study attempts to understand how the selected visual frames worked to communicate the causes, effects, and responses to the massacre and also to press freedom—an ideological construct that news media had a vested interest in advancing. 相似文献
54.
With advanced prediction modes of intra prediction, intra coding of H.264/AVC offers significant coding gains compared with previous video coding standards. It uses an important tool called Lagrangian rate-distortion optimization (RDO) technique to decide the best coding mode for a block, but the computational burden is extremely high. In this paper, we proposed an improved fast intra prediction algorithm including block type selection and mode decision algorithm based on analysis of edge feature of a block. Our algorithm filters out unlikely block type and candidate modes to reduce the RDO calculations. Experimental results showed that the proposed algorithm can reduce the computation complexity of intra prediction from 52.90% to 56.31%, with 0.04 dB PSNR degradation and 2% increase of bit rate. 相似文献
55.
A clinical task-based interview can be seen as a situation where the interviewer–interviewee interaction on a task is regulated
by a system of explicit and implicit norms, values, and rules. This paper describes how documenting and mapping triadic interaction
among the interviewer, the interviewee, and the knowledge negotiated can be used to increase procedural replicability of the
interview and accuracy of drawn conclusions about the interviewee’s thinking process. Excerpts from interviews with 25 inservice
mathematics teachers working on a task to make up a problem whose solution requires division of two fractions are discussed.
The excerpts illustrate the relationship between methodological decisions taken by the interviewer during the interview and
the applicability of the interview output to the research questions. A divergent analysis of the interviews with these teachers,
which spanned over two years and were conducted by four interviewers, is used to offer a framework for analyzing data collected
in clinical task-based interviews. 相似文献
56.
57.
1IntroductionBackground subtraction methods are extensively ex-ploited for moving object detection in videos in manyapplications ,such as traffic monitoring[1],human mo-tion capture[2]and video surveillance[3]. The centralidea behind such methods is to segment foreground ini mage sequences taken from a fixed camera by com-paring each newframe to a model of the scene back-ground . Therefore , correctly and efficiently modelingand updating the background model is one of the mostchallenging aspec… 相似文献
58.
59.
Veronique M. Boscart Lynn McCleary Paul Stolee Linda Sheiban Taucar Jessica Wilhelm Keia Johnson 《Educational gerontology》2020,46(8):461-472
ABSTRACT Nursing Assistants (NAs) are the largest workforce in nursing homes, but often lack adequate preparation for their role. The Living Classroom (LC) is an integrated learning approach, whereby a NA program is delivered in a nursing home (NH) in collaboration with a community college. This paper describes the implementation and evaluation of the LC. Mixed methods were used to gather data from 48 NA students, 5 faculty, and 42 NH staff over 30 weeks. Students, faculty, and nursing home staff described the LC as a positive learning experience. Students’ gerontological knowledge increased over time (p = .0012). Students reported very positive relationships with program mentors and NH residents. The LC provides a unique approach to prepare NAs to work in nursing homes. This model could expand to other educational programs with a gerontology focus. 相似文献
60.
Linda S. Fazio 《Assessment & Evaluation in Higher Education》1985,10(2):147-157
This paper describes and analysies the use of a delphi research methodology to assess faculty perceptions of institutional needs and goals in an osteopathic medical education program. Use of the delphi to educate faculty in the administrative and political functioning of the institution as well as to involve all faculty in the refinement of specific needs and goals is discussed. Full‐time clinical and basic science faculty of the New Jersey School of Osteopathic Medicine provided an example of the varied uses of the delphi research methodology in higher education and specifically in profesiional higher education. The three rounds of the delphi procedure produced faculty consensus on the following institutional variable items: (a) the philosophical and functional orientation of the curriculum; (b) location and design of the physical campus facilities and environment; (c) faculty issues of tenure, promotion, salary and merit; (d) teaching, and the evaluation of teaching; (e) student characteristics and admissions policies; and (f) administrative structure and communication networks. 相似文献